1. Field of the Invention
This invention relates to an umbrella frame device, more particularly to an umbrella frame device with a sleeve member which is operable to move a runner between engaging and disengaging positions.
2. Description of the Related Art
A conventional umbrella is shown to include an elongate stem with an upper elongate hole in which a spring-loaded stop is provided. A runner is sleeved slidably on the stem to support a rib assembly which is mounted on an upper end of the stem. The runner is movable along the stem between an upper position for stretching the rib assembly and a lower position for collapsing the same. At the upper position, the runner is retainingly supported by the stop.
In view of the fact that the stem of the conventional umbrella frame device has to be provided with the hole to receive the stop, a solid structure was not contemplated for the stem. Due to this inherent limitation of the stem, which is a primary part of the umbrella frame device in terms of strength, it is quite difficult to improve the rigidity of the stem, and hence the durability of the umbrella frame device. Moreover, it is uncomfortable to press an end of the stop for collapsing the rib assembly, which has an acute and rigid surface.
The object of the present invention is to provide an umbrella frame device which can be operated conveniently and comfortably to spread and collapse a canopy, and which has a simple construction to facilitate assembly.
According to this invention, the umbrella frame device includes an elongate stem which has an outer surrounding stem surface that extends along and that surrounds an axis in an axial direction. The outer surrounding stem surface has an upper end portion on which a canopy is adapted to be mounted, a lower end portion, and a middle portion between the upper and lower end portions.
A protuberance is disposed on the middle portion adjacent to the upper end portion, extends in the axial direction, and has a slideway thereon. The slideway terminates at an upper edge that forms a shoulder with the middle portion. The shoulder extends inwardly and radially of the upper edge.
A tubular runner is sleeved on and is movable relative to the stem between upper and lower positions respectively for spreading and collapsing the canopy. The runner has inner and outer surrounding runner surfaces opposite to each other in radial directions relative to the axis. The outer surrounding runner surface has a slot which extends radially through the inner surrounding runner surface. The inner surrounding runner surface is movable along the slideway.
A retaining member has a retaining end which is disposed to be movable radially in the slot and which is extendable inwardly of the inner surrounding runner surface to slidably contact the slideway. The retaining end is brought to slip over the upper edge so as to be retained on the shoulder when the inner surrounding runner surface is moved along the slideway relative to the axis from a disengaging position which corresponds to the lower position, to an engaging position which corresponds to the upper position.
A sleeve member has an inner surrounding sleeve surface which surrounds the outer surrounding runner surface, and which is movable relative to the outer surrounding runner surface along the axis. The inner surrounding sleeve surface has a cam surface portion which confronts the retaining member and which is configured to be disengaged from the retaining end of the retaining member when the runner is in the lower position and to depress the retaining end radially with a friction force that arrests the inner surrounding runner surface in the engaging position, while the sleeve member is held against gravity by the retaining member.